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  • #16
    Congratulation on getting your plane flying Ed! It's a great feeling when years of work turn into a first flight.

    You might consider reading Lycoming's break in procedure or at least call and talk to Bob, perhaps you already have. Lycoming says to run the engine at 65% minimum, 70-75% is better, for 50hrs or until oil consumption stabilizes. Those power setting are required for proper ring seating. Continentals usually take less than 10hrs to seat the rings and I imagine Lycs are similar.

    FWF issues are stressful to deal with during phase 1. Good luck!
    Scratch Built 4-place Bearhawk. Continental IO-360, 88" C203 McCauley prop.

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    • #17
      Ed, I think the EFII system is one of the most exciting developments in our arena! I'd be interested to hear your thoughts about the system and your experiences with it. I've flown (and am flying) a single electronic ignition, in my last builds. But I didn't have the 'nads to turn over total engine control to the electrons, yet. Hearing the experiences of trailblazers, like yourself, could sway my opinion!


      Bill

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      • #18
        Ed;

        I am also keenly watching!! Keep us updated! We are keenly interested in efficiency and reliability gains your system provides.

        Also, have you tried retarding the timing to lower CHT's? Although efficiency would take a hit, it might lower your CHT's by forcing some of the combustion process to take place outside the cylinder and into the exhaust allowing you to run a higher power setting for break-in.

        Brooks Cone
        Southeast Michigan
        Patrol #303, Kit build

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        • #19
          Donna asked for temps, so I took a picture today.
          The attached pic was at 60% power. I didn't remember her request at 75%. #3 is always cooler. It might be a probe issue, but all temps read the same at ambient, prior to start.

          Bill
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          This gallery has 1 photos.

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          • Flygirl1
            Flygirl1 commented
            Editing a comment
            Thank you Bill. I flew mine today, HURAH!! At 70 degrees at 3500ft oil went to 211 and my cyl were from 398 to 412. Talked with Mark today and I think at some point we will open up the cowling a bit more. These were at 75% power and 11 GPH fuel burn.

          • Bdflies
            Bdflies commented
            Editing a comment
            I'm feeling a bit guilty about hijacking Ed's first flight thread, but I have to ask; WHAT HAPPENED to your temps?
            I'm not real sure the problem is just exit area. My suspicion is that the cowl exit is a fairly high pressure area.

            Bill

        • #20
          Thanks everyone for the pointers and questions. I have been pretty 'under the weather' the last couple days with a cold (even though the weather has been beautiful here in N Idaho) so sorry for the delay posting.

          I have no way to know things like efficiency with the EFII yet because I have not flown enough. So far my concern has been to keep it running good which I am happy to say it has done very well. We added the lip to the bottom of the cowl at the outlet today but have not had a chance to fly again with my meds and such. Looking forward to trying it though. I might be worrying a bit too much about the CHTs. I start to feel some panic when they start going over about 430.

          As far as the timing is concerned, I have reviewed the curves programmed into the ECUs and they are pretty close the the normal 25 before TDC normally recommended. They advance a few degrees at lower power setting with high RPMs so I doubt that is a problem. Working with the O2 sensor and direct readout of mixture is different for me and I have not determined peak EGTs yet. Just keeping mixture showing somewhere around 12.5:1. I find it interesting that on run-up, there is ZERO drop when switching either one of the ignitions off (and I have confirmed that if I turn them both off the engine quits).

          I do agree moving into the 21st century with the EFII is a good opportunity. Many years ago I worked on many carb, mags, generators, etc. in an airplane engine overhaul shop. I concluded then that a carburetor is a somewhat accidental way to get fuel into an engine, I have also noted that automobiles have been using EFII since about the mid 80s and I have found that they became much more reliable at that point. The EFII system in the airplane is not quite the same in the interest of reliability I think. The big difference is that it is not a closed loop system reacting to the data from the O2 sensor. I think this is due to the fact that with leaded fuel the O2 sensor is not very reliable so for flying we don't want to depend on it.

          The only issue I have had with the EFII so far is that the first start when cold takes a bit, as in several short tries, to get it to light off. Once warm it starts very easy. Robert Paisley's support has been excellent helping to understand the system as well offering improvement. He wants me to send back the main ECU so he can update the programming to allow for better priming during cold starts. We will send it at some point but I don't want to interrupt flying at this point.

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          • #21
            Ed;

            Will you describe for us how you designed your fuel system? Specifically, the fuel return, fuel selector valve, and the pumps required to deliver fuel to the engine?

            Brooks
            Brooks Cone
            Southeast Michigan
            Patrol #303, Kit build

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            • #22
              Ed
              I think the paint scheme is really nice. Well done.

              In your post on 21 May you said the follwoing "....at around 2150-2200 RPMs, Fixed pitch prop and MP about 17" at that RPM. ...."

              Q. What indicated airspeed were you getting for that power settigns and RPM?

              Q. Did you have much of a load on board? 2POB 1/2 or 3/4 fuel etc.

              I have an 0360 to put in my Bearhawk, albeit only std carby and mags at this stage, but i do have a vetterman exhaust.

              Peter
              4 Place scratch built
              plans #1186

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              • #23
                On the fuel system we had to add a fitting to each wing tank for the return line. It was added about 1/2 way between front and aft where there was a big lightening whole in the ribs for easy access. Used the SPRL duplex fuel valve http://www.aircraftspruce.com/catalo...clickkey=87308. Had to plumb it twice because, as I recall we thought the top part of the valve was the feed side but that was wrong. From there the fuel lines go through the gascolator (used the Barrows product), then through the EFII supplied parts: filter, fuel pump manifold with both pumps, then another filter on the engine side of the firewall then through the injector rails, then the pressure regulator back to the fuel valve. I all works good. We also used the optional EFII Buss Manager which automatically switches to pump two if number on drops out. This operation is verified at each start since when first powered up there is no pressure so it switches to number two. Then we switch to number two and back to one and it holds.

                As far as the performance at very low power, I was seeing about 95 knots at about 1/2 fuel solo but I am big at about 285 lbs. The prop is a Catto 80X52. We do have the Vetterman crossover exhaust system. Airplane feels great at that speed and does not feel like it is mushing along.

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                • #24
                  Ed, I remembered your setup today, while reading about O2 sensor problems with leaded fuel. Are you still running leaded gas? Has the sensor held up reliably? Have you solved your high temp issues? Anything new to add about your experience with the EFII system?
                  Thanks,

                  Bill

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                  • #25
                    Have only been running 100ll and O2 sensor is still fine. Only 70 hours so far though. I run it well lean of peak in cruise burning only 6-6.5 GPH. CHTs run in the 350 range in cruise and I find that if I run a little richer, about 12:1 AFR vs 12.5-13, it helps keep temps below 400 in a hard climb. All in all, it runs great. Did you see the write-up in Beartracks?

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                    • #26
                      Thanks Ed. I did read your fine article! Glad to hear that all is good! I’m very interested in your installation and just want to read anything that you care to share.

                      Bill

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